Screening for abdominal aortic aneurysm in Canada: Review and position statement of the Canadian Society for Vascular Surgery

Routine Abdominal Aortic Examination During Echocardiographic Studies Detects Significant Numbers of Abdominal Aortic Aneurysm and Should be a Part of Routine Echocardiographic Examinations

BACKGROUND

Early detection and follow-up of abdominal aortic aneurysm (AAA) are important and can be lifesaving. The goal of this study was to evaluate if routine abdominal aorta screenings during echocardiograms can be helpful in detecting asymptomatic abdominal aortic aneurysm.

METHODS

We retrospective studied consecutive patients who were sent for outpatient routine echocardiograms for various clinical reasons in 2015-2017 until we reached a total of 1000 patients. Starting from the subcostal and then proceeding to the abdomen, a long-axis screening of the abdominal aorta was attempted on all of the patients after the echocardiogram was completed. No patient preparation was given. Imaging began from the subcostal view and proceeded caudally with images obtained every 1-2 cm. Measurement of the aortic diameter was performed from the longitudinal plane using the leading-edge-to-leading-edge method.

RESULTS

The age range was 33-96 years with a median age of 72.4. A total of 273 (27.3%) patients did not have an appropriate window to evaluate AAA. Among the remaining 727 screenings, 18 (2.4%) had dilatation of abdominal aorta or AAA. The dilatation and aneurysms ranged between 2.5 and 4.5 cm in size. Abnormal aortic diameters were as follows: 5 (27.7%) were between 2.5 and 2.9 cm, 6 (33.3%) between 3 and 3.4 cm, 1 (5.5%) between 3.5 and 3.9, 5 (27.7%) between 4.0 and 4.4 cm, and 1 (5.5%) between 4.5 and 4.9 cm.

CONCLUSIONS

Performing routine abdominal aortic examinations during routine echocardiographic exams can detect a significant amount of abdominal aortic aneurysm which can be lifesaving. We suggest adding abdominal aortic assessment to routine echocardiographic examination.

Trends in Incidence of Abdominal Aortic Aneurysm Rupture, Repair, and Mortality in Nova Scotia

BACKGROUND

The purpose of this study was to examine sex-based trends in incidence of elective abdominal aortic aneurysm (AAA), ruptured AAA, ruptured AAA repair, and AAA-related mortality.

METHODS

A retrospective analysis of patients presenting with AAA from 2005 to 2015 was conducted. Rates of elective AAA repair, ruptured AAA, ruptured AAA repair, and mortality were obtained from linking provincial administrative data using medical services insurance billing number. The age-adjusted incidence of elective AAA repair, overall rate of ruptured AAA, ruptured AAA repair, and AAA-related mortality was calculated for each sex based on Canadian census estimates, adjusted to the Canadian standard population. Weighted linear regression was performed to analyze trends in incidence over time.

RESULTS

One thousand nine hundred eighty-six elective AAA repairs were identified, of which 1,098 were repaired open and 898 underwent endovascular abdominal aneurysm repair (EVAR). Five hundred and seventy ruptured AAAs were identified, of which 295 (52%) were repaired: 259 open and 36 EVAR. The proportion of ruptured AAA that was repaired did not change over time (P = 0.54). The proportion repairs performed using EVAR increased significantly in both elective (P < 0.001) and rupture repairs (P < 0.001). During the study period, 662 patients died of AAA-associated mortality. The average incidence of elective AAA repair in men was 29.3 (95% confidence interval (CI): 27.8 to 30.8) per 100,000 and decreased over time (P = 0.04), whereas the average incidence in women was 9.2 [8.3 to 10.0] and stable (P = 0.07). The incidence of open elective AAA repair was 10.5 [9.9-11.1] with a decreasing trend over time (P < 0.001) and EVAR was 9.0 (8.5-9.6) with an increasing trend over time (P < 0.001). A decreasing trend of overall ruptured AAA (5.4 [5.0-5.9], P < 0.001), ruptured AAA repair (2.9 [2.5-3.2], P = 0.02), and of AAA-related mortality (6.2 [5.8-6.8], P < 0.001) was found, with consistent trends in both sexes. The incidence of open ruptured AAA repair decreased over time (P = 0.001) whereas the incidence of ruptured EVAR remained stable (P = 0.23).

CONCLUSIONS

The incidence of elective AAA repair is decreasing in males but not females, whereas the incidence of rupture has decreased in both sexes. This has translated into reduced incidence of AAA-related mortality. Increased adoption of EVAR for ruptured AAA should continue these trends.

Infrarenal Abdominal Aortic Aneurysm

Abdominal aortic aneurysms are found in up to 6% of men and 1.7% of women over the age of 65 years and are usually asymptomatic. The natural history of aortic aneurysms is continued dilation leading to rupture, which is associated with an overall 80% mortality. Of the patients with ruptured aneurysms that undergo intervention, half will not survive their hospitalization. Reduction in aneurysm mortality is therefore achieved by prophylactic repair during the asymptomatic period. On a population-based level, this is supported by abdominal aortic aneurysm screening programs. Approximately 60% of abdominal aortic aneurysms are confined to the infrarenal portion of the aorta and are amenable to repair with off-the-shelf endovascular devices. Endovascular techniques have now replaced open surgery as the primary modality for aneurysm repair.

Dying to Get There: Patients Who Reside at Increased Distance from Tertiary Center Experience Increased Mortality Following Abdominal Aortic Aneurysm Rupture

BACKGROUND

Centralization of vascular surgery care for Ruptured Abdominal Aortic Aneurysms (RAAAs) to high-volume tertiary centers may hinder access to timely surgical intervention for patients in remote areas. The objective of this study was to determine the association between distance from vascular care and mortality from RAAAs in the province of Nova Scotia, Canada.

METHODS

A retrospective cohort study of all RAAAs in Nova Scotia between 2005 and 2015 was performed through linkage of administrative databases. Patients were divided into groups by estimated travel time from their place of residence to the tertiary center (<1 hr and ≥1 hr) using geographic information software. Baseline and operative characteristics were identified for all patients through available databases and completed through chart review. Mortality at home, during transfer to the vascular center, and overall 30-day mortality were compared between groups using t-test and chi-squared test, as appropriate. Multivariable logistic regression analysis was used to calculate the independent effect of travel time on survival outcomes.

RESULTS

A total of 567 patients with RAAA were identified from 2005-2015, of which 250 (44%) resided <1 hr travel time to the tertiary center and 317 (56%) resided ≥1 hr. On multivariable analysis, travel time ≥1 hr from vascular care was an independent predictor of mortality at home (odds ratio [OR] 1.68, 95% confidence interval [CI] 1.07-2.63, P = 0.02), mortality prior to operation (OR 2.64, 95% CI 1.81-3.83, P < 0.001), and overall 30-day mortality (OR 1.61, 95% CI 1.10-2.37, P = 0.02). In patients who received an operation (n = 294), there was no association between increased travel time and mortality (OR 1.02, 95% CI 0.60-1.73, P = 0.94).

CONCLUSIONS

Travel time ≥1 hr to the tertiary center is associated with significantly higher mortality from ruptured abdominal aortic aneurysm (AAA). However, there was no difference in overall chance of survival between groups for patients that underwent AAA repair. Therefore, strategies to facilitate early detection, and timely transfer to a vascular surgery center may improve outcomes for patients with RAAA.

Impact of an emergency endovascular aneurysm repair protocol on 30-day ruptured abdominal aortic aneurysm mortality

OBJECTIVE

To characterize the longstanding impact of an emergency endovascular aneurysm repair (EVAR) protocol for ruptured abdominal aortic aneurysm (rAAA) on 30-day mortality.

METHODS

All adult patients with an rAAA who underwent a surgical or endovascular intervention at a tertiary care center between March 2001 and December 2018 were evaluated. An emergency EVAR protocol was introduced in January 2004. The primary outcome was 30-day mortality, which was calculated using risk-adjusted logistic regression for the preprotocol and postprotocol periods. A risk-adjusted cumulative sum analysis examined changes in 30-day mortality after protocol implementation.

RESULTS

We identified 376 patients with rAAA between 2001 and 2018 (75 preprotocol and 301 postprotocol), with a decreasing incidence of rAAA during the study period. The introduction of the protocol in 2004 was associated with increased EVAR use (63.6% vs 6.7%; P < .001). Patients managed according to the protocol were more frequently unstable (systolic blood pressure [SBP] of ≤80 mm Hg, 46.5% postprotocol vs 22.7% preprotocol; P < 0.001), with a lower average SBP (87.4 mm Hg postprotocol vs 106 mm Hg preprotocol; P < .001) and worse renal function (estimated glomerular filtration rate 61.5 mL/min postprotocol vs 83.2 mL/min preprotocol; P < .001). The risk-adjusted 30-day mortality was 23.2% with the emergency EVAR protocol, versus 35.8% preprotocol (P = .0727). A subgroup analysis demonstrated improved the 30-day mortality for unstable patients (SBP of ≤80 mm Hg) at 38.0% (vs 62.4% preprotocol introduction; P = .0190). A cumulative sum analysis demonstrated worse than expected mortality outcomes in the preprotocol period, and stability of surgical performance over 15 years after protocol introduction.

CONCLUSIONS

On reflection of a 17-year experience with EVAR for rAAA, the implementation of an emergency EVAR protocol demonstrated stable surgical performance for all patients with an rAAA and evidence of improved 30-day mortality for unstable patients with an rAAA. Since the protocol introduction, EVAR has become a mainstay intervention and, despite an increase in comorbid patients, the overall incidence of rAAA is declining. EVAR should be considered the first-line intervention for the appropriate patient unstable with an rAAA.

Screening for abdominal aortic aneurysms in Canada: 2020 review and position statement of the Canadian Society for Vascular Surgery

Abdominal aortic aneurysms (AAAs) remain a major risk to patients, despite level 1 evidence for screening to prevent rupture events and decrease mortality. In 2007, the Canadian Society for Vascular Surgery (CSVS) published a review and position statement for AAA screening in Canada. Since that publication, there have been a number of updates in the published literature affecting screening recommendations. In this paper, we present a review of some of the controversies in the AAA screening literature to help elucidate differences in the various published screening guidelines. This article represents a review of the data and updated recommendations for AAA screening in the Canadian population on behalf of the CSVS.

Les anévrismes de l’aorte abdominale (AAA) continuent de poser un risque majeur pour les patients, malgré des données probantes de niveau 1 à l’appui du dépistage pour prévenir les ruptures et réduire la mortalité. En 2007, la Société canadienne de chirurgie vasculaire (SCCV) a publié une revue et un énoncé de position sur le dépistage de l’AAA au Canada. Depuis lors, plusieurs mises à jour ont paru dans la littérature et elles ont un impact sur les recommandations relatives au dépistage. Dans le présent article, nous présentons une synthèse de quelques controverses soulevées dans la littérature sur le dépistage de l’AAA afin d’expliquer les différences entre les diverses lignes directrices publiées à ce sujet. Cet article propose au nom de la SCCV une revue des données probantes et des recommandations à jour sur le dépistage de l’AAA dans la population canadienne.

Screening Program of Abdominal Aortic Aneurysm

In Europe, the prevalence of abdominal aortic aneurysms (AAAs) in the elderly population (≥65 year old) has declined in the past decades to <4%. Aneurysmal degeneration of the aorta is a serious and potentially life-threatening vascular disease. Abdominal aortic aneurysms typically develop subclinically and often only become symptomatic when complicated by impending rupture. Most AAAs are discovered incidentally while investigating for an unrelated pathology. Ruptured AAA is the tenth leading cause of death in Belgium (0.32% of all deaths in 2014). Health-care providers have emphasized the importance of early detection of AAA and elective repair when the rupture risk outweighs operative risk (usual diameter threshold of 55 mm). Routine AAA screening programs, consisting of a single abdominal ultrasonography at the age of 65 years, aim to reduce the number of AAA-related deaths. Does population-based ultrasound screening for AAA achieve its objective and is it cost-effective? This literature review tries to answer these challenging questions.

Risk factors and short and medium-term survival after open and endovascular repair of abdominal aortic aneurysms

Background

Infrarenal abdominal aortic aneurysms (AAA) are responsible for high rates of rupture-associated morbidity and mortality and can be treated by open or endovascular surgery.

Objectives

To analyze risk factors and survival associated with surgical and endovascular AAA treatment methods.

Methods

A retrospective, longitudinal study involving 41 patients who underwent endovascular or open AAA repair, whether elective or emergency, over a 48-month period, with analysis of preoperative comorbidities, 30-day and 1-year survival, in-hospital mortality, length of hospital stay, transfusion of blood products, duration of surgery, and development of acute kidney failure. Inferential statistics and survival analysis considered a 95% CI and p < 0.05 as significant.

Results

Twelve of the 41 patients were treated with open surgery and 29 with endovascular techniques. The majority were male (75%), with an average age of 71 (range: 56 – 90 years). There were no differences in demographic or risk factors between the groups. Overall survival rates for open and endovascular repair were different for both 30 days (37 vs. 72%, p = 0.01) and 360 days (37 vs. 67%, p = 0.01). However, survival rates in elective cases were similar at 30 days (71 vs. 76%, p = 0.44) and 360 days (both 71%, p = 0.34). Endovascular repair showed shorter length of hospital stay (3.0 vs. 4.4 days; p = 0.02) and duration of surgery (111 vs. 163 min; p < 0.01) compared to open repair.

Conclusions

There was no difference in short- or medium-term survival of AAA patients treated electively with endovascular or open surgery. Hospital stays and duration of surgery were both shorter with minimally invasive treatment.

[Validity of the abdominal ecography in primary care for detection of aorta abdominal aneurism in male between 65 and 75 years]

OBJECTIVE

To determine the usefulness of ultrasound examination in Primary Care (PC) for the detection of abdominal aortic aneurysm (AAA) in male patients from 65-75 years old, as well as the consistency between observers on the diagnosis between general practitioners and the reference specialty in this area, Vascular Surgery. To estimate the prevalence of AAA in that population and its association with risk factors.

DESIGN

Cross-sectional descriptive study.

LOCATION

Healthcare Centres of Coto and Calzada II (Gijón, Spain).

PARTICIPANTS

Males born between 1 January 1939 and 31 December 1950.

INTERVENTIONS

From the 2,511 males found, 407 were selected using stratified random sampling. Aortic diameter was measured, with those ≥3cm and 20% from the <3cm being referred for a second measurement by a vascular surgeon.

VARIABLES

Dependent: presence/absence of aneurism. Independent: age, abdominal perimeter, smoking, arterial hypertension, diabetes, dyslipidaemia, familial cases of AAA, cerebrovascular accident, and coronary disease. The analysis was performed using Bayesian inference with models for proportions and a multivariate logistic regression.

RESULTS

From 304 ultrasound scans performed, 13 were referred with suspicion of AAA, and 63 with were within normal. The sensitivity was 93.3% and specificity 98.5% with a 95% credibility interval (CredI) of 75.4-99.9%, and 94.3-100%, respectively. The prevalence was 4.6% (95% CredI: 2.5-7.2%, and the intraclass correlation coefficient between PC and Vascular Surgery was 0.88 (95% CredI: 0.79-0.94). Age, smoking, dyslipidaemia, and diabetes tended to increase the odds of prevalence of AAA.

CONCLUSION

The ultrasound performed by GPs for the detection of AAA had high diagnostic validity. Further studies on the effectiveness should be conducted in order to assess the appropriateness of introducing a system of early detection of AAA in the risk population.

Prevalence of Elective and Ruptured Abdominal Aortic Aneurysm Repairs by Age and Sex From 2003 to 2016 in Ontario, Canada

IMPORTANCE

Age and sex are important considerations in assessing and individualizing therapy for abdominal aortic aneurysm (AAA) repair.

OBJECTIVE

To determine the prevalence of open and endovascular elective AAA (EAAA) and ruptured AAA (RAAA) repair by age and sex.

DESIGN, SETTING, AND PARTICIPANTS

In this retrospective, population-based, cross-sectional, time-series analysis in Ontario, Canada, from April 1, 2003, to March 31, 2016, all patients undergoing AAA repair who were older than 39 years were included.

EXPOSURES

Elective AAA and RAAA repair with open surgical repair (OSR) or endovascular aortic repair (EVAR).

MAIN OUTCOMES AND MEASURES

Age- and sex-standardized rates of EAAA and RAAA repair with OSR and EVAR.

RESULTS

From 2003 to 2016, 19 489 EAAA repairs (12 232 [63%] OSR and 7257 [37%] EVAR) and 2732 RAAA repairs (2466 [90%] OSR and 266 [10%] EVAR) were identified. The mean (SD) age was 72.7 (8.1) years in the EAAA subgroup and 73.5 (8.9) years in the RAAA subgroup; 15 813 patients (81%) in the EAAA subgroup and 2178 (80%) in the RAAA subgroup were men. The rates of EAAA by age quintile and sex decreased over the study period except among patients older than 79 years (1.3 per 100 000 population in 2003 to 2.2 per 100 000 population in 2016; 70% increase; P < .001). The rates of elective OSR decreased across all age and sex subgroups (range, 38%-74% decrease; P ≤ .009 for all subgroups) except among patients older than 79 years (1.3 per 100 000 population at baseline to 0.56 per 100 000 population in the second quarter of 2016; 53% decrease; P = .05). The rates of elective EVAR significantly increased across all age and sex subgroups (range, 566%-1585% increase; P ≤ .04 for all subgroups). Elective EVAR became the dominant treatment approach for aneurysms in men around 2010, whereas it maintained parity among women in 2016. The RAAA repair rate decreased over the study period in all subgroups (range, 32%-91% decrease; P ≤ .001 for all subgroups), but the decrease was not significant among women (80% decrease; P = .08). Similarly, the rates of ruptured OSR decreased among all subgroups (range, 47%-91% decrease; P < .001), but the decrease was not significant among women (87% decrease; P = .54). Ruptured EVAR showed significant uptake in all subgroups.

CONCLUSIONS AND RELEVANCE

Among patients with AAA in Ontario, Canada, use of EVAR appeared to increase from 2003 to 2016, whereas OSR use appeared to decrease. These findings were most pronounced among elective procedures for men and older patients. The delayed increase in the use of EVAR among women may reflect continued anatomical constraints for women seeking elective repair.

[Usefulness and reliability of abdominal point of care ultrasound in family practice (2): Large abdominal vessels, spleen, nephrourological and gynecological ultrasound]

This article is a continuation of the review initiated in the previous issue about the usefulness of point of care ultrasound in Primary Care, completing the scenarios of large abdominal vessels, spleen, nephrourological and gynecological ultrasound.

[Identifying barriers to screening for abdominal aortic aneurysm in general practice: Qualitative study of 14 general practitioners in Paris]

INTRODUCTION

Abdominal aortic aneurysm (AAA) is a silent pathology with often fatal consequences in case of rupture. AAA screening, recommended in France and many other countries, has shown its effectiveness in reducing specific mortality. However, AAA screening rate remains insufficient.

OBJECTIVE

To identify barriers to AAA screening in general practice.

MATERIAL AND METHOD

Qualitative study carried out during 2016 among general practitioners based in Paris.

RESULTS

Fourteen physicians were included. Most of the barriers were related to the physician: unawareness about AAA and screening recommendations, considering AAA as a secondary question not discussed with the patient, abdominal aorta not included in cardiovascular assessment, no search for a familial history of AAA, AAA considered a question for the specialist, lack of time, lack of training, numerous screenings to propose, oversight. Some barriers are related to the patient: unawareness of the pathology and family history of AAA, refusal, questioning the pertinence of the doctor's comments, failure to respect the care pathway. Others are related to AAA: source of anxiety, low prevalence, rarity of complications. The remaining barriers are related to screening: cost-benefit and risk-benefit ratios, sonographer unavailability, constraint for the patient, overmedicalization.

CONCLUSION

Information and training of general practitioners about AAA must be strengthened in order to optimize AAA screening and reduce specific mortality.

Screening key genes for abdominal aortic aneurysm based on gene expression omnibus dataset

Background

Abdominal aortic aneurysm (AAA) is a common cardiovascular system disease with high mortality. The aim of this study was to identify potential genes for diagnosis and therapy in AAA.

Methods

We searched and downloaded mRNA expression data from the Gene Expression Omnibus (GEO) database to identify differentially expressed genes (DEGs) from AAA and normal individuals. Then, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis, transcriptional factors (TFs) network and protein-protein interaction (PPI) network were used to explore the function of genes. Additionally, immunohistochemical (IHC) staining was used to validate the expression of identified genes. Finally, the diagnostic value of identified genes was accessed by receiver operating characteristic (ROC) analysis in GEO database.

Results

A total of 1199 DEGs (188 up-regulated and 1011 down-regulated) were identified between AAA and normal individual. KEGG pathway analysis displayed that vascular smooth muscle contraction and pathways in cancer were significantly enriched signal pathway. The top 10 up-regulated and top 10 down-regulated DEGs were used to construct TFs and PPI networks. Some genes with high degrees such as NELL2, CCR7, MGAM, HBB, CSNK2A2, ZBTB16 and FOXO1 were identified to be related to AAA. The consequences of IHC staining showed that CCR7 and PDGFA were up-regulated in tissue samples of AAA. ROC analysis showed that NELL2, CCR7, MGAM, HBB, CSNK2A2, ZBTB16, FOXO1 and PDGFA had the potential diagnostic value for AAA.

Conclusions

The identified genes including NELL2, CCR7, MGAM, HBB, CSNK2A2, ZBTB16, FOXO1 and PDGFA might be involved in the pathology of AAA.

Abdominal aortic aneurysm: Sex differences

OBJECTIVE

Abdominal aortic aneurysm (AAA) predominantly affects an elderly male population. Even so, AAA appears more detrimental in women, who experience a higher risk of aneurysm rupture and a worse outcome after surgery than men. Why women are privileged from yet are worse off once affected has been attributed to an effect of sex hormones. This review summarizes the knowledge of sex differences in AAA and addresses the changes in the aneurysm wall from a gender perspective.

METHOD

Standard reporting guidelines set by the PRISMA Group were followed to identify studies examining AAA from a gender perspective. Relevant reports were identified using two electronic databases: PubMed and Web of Science. The systematic search was performed in two stages: firstly, using the terms AAA and gender/sex/women; and secondly, adding the terms "elastin", "collagen" and "vascular smooth muscle cells", in order to filter the search for studies relevant to our focus on the aneurysm wall.

CONCLUSION

Current studies support the theory that sex has an effect on aneurysm formation, yet are inconclusive about whether or not aneurysm formation is dependent on female/male sex hormones or a lack thereof. The studies in women are scarce and out of those most reports primarily address other end-points, which limit their ability to illuminate an effect of sex on aneurysm formation. The complexity of the human menstrual cycle and menopausal transition are difficult to mimic in animal models, which limit their applicability to AAA formation in humans.

Experiences of the screening process and the diagnosis abdominal aortic aneurysm among 65-year-old men from invitation to a 1-year surveillance

The prevalence of abdominal aortic aneurysm (AAA) is reported to be 2.2%-8% among men >65 years. During recent years, screening programs have been developed to detect AAA, prevent ruptures, and thereby saving lives. Therefore, most men with the diagnosis are monitored conservatively with regular reviews. The objective of the study was to describe how men diagnosed with abdominal aortic aneurysm <55 mm discovered by screening experience the process and diagnosis from invitation to 1 year after screening. A total of eleven 65-year-old men were included in three focus groups performed in a University Hospital in Sweden. These were qualitatively analyzed using manifest and latent content analysis. The experience of the screening process and having an abdominal aortic aneurysm in a long-term perspective revealed three categories: "trusting the health care system," emphasizing the need for continual follow-ups to ensure feelings of security; "the importance size," meaning that the measure was abstract and hard to understand; and "coping with the knowledge of abdominal aortic aneurysm," denoting how everyday life was based mostly on beliefs, since a majority lacked understanding about the meaning of the condition. The men want regular surveillance and surrendered to the health care system, but simultaneously experienced a lack of support thereof. Knowing the size of the aorta was important. The men expressed insecurity about how lifestyle might influence the abdominal aortic aneurysm and what they could do to improve their health condition. This highlights the importance of communicating knowledge about the abdominal aortic aneurysm to promote men's feelings of security and giving space to discuss the size of the aneurysm and lifestyle changes.

Abdominal aortic aneurysm screening program using hand-held ultrasound in primary healthcare

We determined the feasibility of abdominal aortic aneurysm (AAA) screening program led by family physicians in public primary healthcare setting using hand-held ultrasound device. The potential study population was 11,214 men aged ≥ 60 years attended by three urban, public primary healthcare centers. Participants were recruited by randomly-selected telephone calls. Ultrasound examinations were performed by four trained family physicians with a hand-held ultrasound device (Vscan^®). AAA observed were verified by confirmatory imaging using standard ultrasound or computed tomography. Cardiovascular risk factors were determined. The prevalence of AAA was computed as the sum of previously-known aneurysms, aneurysms detected by the screening program and model-based estimated undiagnosed aneurysms. We screened 1,010 men, with mean age of 71.3 (SD 6.9) years; 995 (98.5%) men had normal aortas and 15 (1.5%) had AAA on Vscan^®. Eleven out of 14 AAA-cases (78.6%) had AAA on confirmatory imaging (one patient died). The total prevalence of AAA was 2.49% (95%CI 2.20 to 2.78). The median aortic diameter at diagnosis was 3.5 cm in screened patients and 4.7 cm (p<0.001) in patients in whom AAA was diagnosed incidentally. Multivariate logistic regression analysis identified coronary heart disease (OR = 4.6, 95%CI 1.3 to 15.9) as the independent factor with the highest odds ratio. A screening program led by trained family physicians using hand-held ultrasound was a feasible, safe and reliable tool for the early detection of AAA.

Contemporary Applications of Ultrasound in Abdominal Aortic Aneurysm Management

Ultrasound (US) is a well-established screening tool for detection of abdominal aortic aneurysms (AAAs) and is currently recommended not only for those with a relevant family history but also for all men and high-risk women older than 65 years of age. The advent of minimally invasive endovascular techniques in the treatment of AAAs [endovascular aneurysm repair (EVAR)] has increased the need for repeat imaging, especially in the postoperative period. Nevertheless, preoperative planning, intraoperative execution, and postoperative surveillance all mandate accurate imaging. While computed tomographic angiography and angiography have dominated the field, repeatedly exposing patients to the deleterious effects of cumulative radiation and intravenous nephrotoxic contrast, US technology has significantly evolved over the past decade. In addition to standard color duplex US, 2D, 3D, or 4D contrast-enhanced US modalities are revolutionizing AAA management and postoperative surveillance. This technology can accurately measure AAA diameter and volume, and most importantly, it can detect endoleaks post-EVAR with high sensitivity and specificity. 4D contrast-enhanced US can even provide hemodynamic information about the branch vessels following fenestrated EVARs. The need for experienced US operators and accredited vascular labs is mandatory to guarantee the reliability of the results. This review article presents a comprehensive overview of the literature on the state-of-art US imaging in AAA management, including post-EVAR follow-up, techniques, and diagnostic accuracy.

[Abdominal aneurism screening in Primary Care]

OBJECTIVES

To obtain the percentage of abdominal aortic aneurism (AAA) determined in men between 65-74 years old in a health centre using ultrasound, and to describe the distribution of risk factors in the whole sample and in patients with aneurism, as well as determining how many AAA are confirmed at the hospital and those cases of uncertain diagnosis.

PATIENTS AND METHOD

A cross-sectional study conducted on patients included from September 2014 to February 2015. From a total of 212 randomised patients, a clinical interview and abdominal ultrasound were performed on 115 men, aged 65 to 74, telephone-recruited from a total of 171 that fulfilled inclusion criteria.

RESULTS

An infra-renal AAA was found in 2.6% of the sample (95% CI 0.54-7.4). Just over half (51.3%) of the sample had arterial hypertension, and 76.1% were smokers or former smokers. The 3 AAA found, one of which had an initial doubtful diagnosis, were confirmed by the Hospital Universitario Fundación Jiménez Díaz. There were no losses. All of the patients with AAA were active smokers and had at least one other risk factor.

CONCLUSION

The percentage of infra-renal AAA in the sample was lower than expected, but higher than the percentage found in other studies that did not consider smoking in the inclusion criteria.

Delayed complication of abdominal aortic stent: a rare complication

We hereby present a case of recurrent abdominal aortic aneurysm due to endoleak to outline complications and secondary intervention strategies post endovascular aneurysm repair.

Geographic disparities in the burden of ruptured and unruptured abdominal aortic aneurysms

BACKGROUND

The province of Saskatchewan presents unique challenges for the care of ruptured abdominal aortic aneurysms (AAAs), including variable access to health care resources and long transportation distances to tertiary vascular care. This study assessed the rates of ruptured and total AAA to determine regional variations within Saskatchewan and ascertain whether there are areas of high AAA prevalence that would possibly benefit from the implementation of a targeted screening program.

METHODS

All diagnoses of AAA from 2001 to 2012 in the province of Saskatchewan were reviewed, with patients grouped by health region of residence. Diagnoses of ruptured and unruptured AAAs were obtained from the Saskatchewan Discharge Abstracts Database, Medical Services Billings Claims data, and Vital Statistics data.

RESULTS

During the study period, 6163 AAAs were diagnosed. The provincial age-adjusted rate of AAA was 53.0/100,000 person-years (95% confidence interval, 48.8-57.6). The highest age-adjusted rate of AAA was found in the Five Hills Health Region (FHHR), at 63.1/100,000 person-years (95% confidence interval, 57.6-69.0), which was significantly higher than the provincial average (P < .05). The rate of ruptured AAA in FHHR was nearly twofold higher than the provincial average (6.0 vs 2.9/100,000 person-years, respectively).

CONCLUSIONS

There are significant geographic variations in the prevalence of AAA in the province of Saskatchewan, with the highest rate of AAA found in the FHHR.

Screening for abdominal aortic aneurysm

Guidelines are systematically developed statements to assist patients and providers in choosing appropriate health care for specific clinical conditions. Consensus exists across guidelines on one-time screening of elderly men to detect and treat abdominal aortic aneurysm (AAA) ≥5.5 cm. However, the recommendations regarding other age groups, imaging intervals for small AAAs, inclusion of women, and cost-effectiveness have not been universally adopted. As many countries are considering the initiation of an AAA screening program, this is an overview on the current status of such programs.

Ultrasound diagnostics of the abdominal aorta: English version

BACKGROUND AND OBJECTIVES

The ideal method for screening investigations is one which is as free as possible from side effects, is easily learnt, and can therefore be broadly used to detect abdominal aortic aneurysms (AAA) with a high degree of certainty. Although ultrasonography fulfils these criteria, the measurement method is not standardized. Different measurement methods are used in ultrasonography as well as in computed tomography (CT) studies and the measurement method is actually described sufficiently in only 57 % of cases.

METHODS

This article provides a critical review of the current literature on measurement methods and the validity of ultrasonography for the determination of aortic diameter, particularly in AAA, and presents the measurement principles for making measurements as precisely as possible.

RESULTS AND CONCLUSION

The most precise determination of aortic diameter is carried out by electrocardiogram (ECG) gating according to the leading-edge method with orthogonal slicing. Within the framework of screening investigations, sufficient measurement precision can be achieved by adherence to orthogonal slicing. Using these standardized measurement methods, ultrasonography shows valid and reproducible results even compared with CT and is the method of choice in screening investigations for AAA.

To be under control: a qualitative study of patients' experiences living with the diagnosis of abdominal aortic aneurysm

BACKGROUND

Abdominal aortic aneurysm can be treated using 3 different methods: open repair, endovascular aortic repair, or conservative treatment with regular monitoring and postponement of surgery until the aneurysm is greater than 55 mm. Conservative treatment entails living with the knowledge that an aneurysm is present while undergoing annual outpatient follow-up.

AIM

This study describes patients' experiences of living with the knowledge that they have an aneurysm for which they are receiving conservative treatment.

METHODS

A qualitative, phenomenological-hermeneutic approach was used. Interviews were conducted between April 2007 and December 2008 with 10 patients diagnosed with abdominal aortic aneurysm less than 55 mm. The interpretation and analysis process involved 3 steps: (1) naive reading and understanding, (2) structural analysis, and (3) comprehensive understanding.

FINDINGS

Five themes based on subthemes were identified: (a) sudden knowledge of a hitherto undetected condition, (b) putting your life in someone else's hands, (c) waiting in limbo-feeling secure despite concerns, (d) life is at stake, and (e) feeling obliged not to cause worry.

CONCLUSION

Living with a diagnosis of abdominal aortic aneurysm implies awareness of having an invisible, life-threatening disease and a sense of being subjected to suffering. We found that patients searched for answers about how to influence the growth of the aneurysm in their everyday life. They avoided thoughts about the aneurysm and struggled to live life as usual.

[Feasibility of hand-held-ultrasonography in the screening of abdominal aortic aneurysms and abdominal aortic atherosclerosis]

BACKGROUND AND OBJECTIVE

To determine the prevalence of abdominal aortic aneurysm (AAA) and abdominal aortic atheromatosis (AA-At) using a hand-held ultrasound by a general practitioner in the public Primary Health Care system.

PATIENTS AND METHOD

Pilot study that prospectively studied a cohort of men over 50 years with cardiovascular risk factors: active smokers, former smokers, or hypertensive patients, attended in primary health care center. The general practitioner completed an ultrasonography training in an Ultrasound Unit under supervision of experienced radiologists using an standard ultrasound equipment and hand-held ultrasound (VScan(®), General Electric, USA). One hundred and six patients participated in the study and all imaging data recorded were blindly evaluated by a radiologist in order to establish the concordance in the interpretation of images between general practitioner and radiologist. The kappa index was calculated to study the agreement on the presence or absence of AAA and AA-At.

RESULTS

We observed a prevalence of 5.88% of AAA. Kappa index for concordance in AAA diagnosis was absolute (κ = 1.0), with a sensitivity and specificity of 100%. Otherwise, the general practitioner identified 59 patients (58.4%) with AA-At, while radiologist identified 39 (38.6%) in the image review, with moderate concordance (κ = .435), sensitivity 89.74% and specificity 57.14%. Hypercholesterolemia (odds ratio [OR] 2.61; 95% confidence interval [95% CI] 0.92-7.39) and diabetes mellitus (OR 3.35; 95%CI 0.89-12.55) were independent risk factors for AA-At development in logistic regression.

CONCLUSIONS

After an adequate training in ultrasonography, hand-held ultrasound is a useful tool for AAA screening in Primary Care. Its simplicity, security, validity, cost-effectiveness and acceptance by the general population, makes it a feasible tool for cardiovascular risk assessment.

Correção endovascular do aneurisma da aorta abdominal: análise dos resultados de único centro

OBJETIVO: Avaliar os resultados clínicos imediatos e em médio prazo do tratamento endovascular em pacientes portadores de aneurisma da aorta abdominal em um centro de referência para doenças cardiovasculares. MATERIAIS E MÉTODOS: Estudo retrospectivo de uma série de pacientes submetidos a tratamento endovascular de aneurisma da aorta abdominal, no período de janeiro de 2009 a julho de 2010. Foram avaliados as características demográficas, o sucesso técnico, o sucesso terapêutico, a morbimortalidade, as complicações e a taxa de reintervenções perioperatórias imediatos, e após um ano de acompanhamento. RESULTADOS: Foram analisados 102 pacientes consecutivos com idade média de 72 ± 9 anos, sendo 79% deles do sexo masculino. Houve sucesso técnico em 97,1% e êxito terapêutico em 81% dos casos. A mortalidade perioperatória foi de 0,9% e a anual, de 7,8%. Foram necessárias reintervenções em 18,8% dos pacientes durante o seguimento. CONCLUSÃO: Em nosso estudo, os resultados obtidos justificam a realização desse procedimento nos pacientes com anatomia adequada.

Reproducibility of ultrasound measurement of the abdominal aorta

BACKGROUND

Abdominal aortic aneurysm (AAA) screening and surveillance programmes use ultrasound imaging to measure the anteroposterior (AP) diameter of the infrarenal aorta. The aim of this study was to examine potential observer bias and variability in ultrasound measurements.

METHODS

Studies were identified for review via a MEDLINE database search (1966-2009). References supplied in accessed papers were also checked for potential relevance. Consistent search terminology, and inclusion and exclusion criteria were used to ensure quality of data. Nine papers were available to review.

RESULTS

Variation in intraobserver repeatability and interobserver reproducibility was identified. Six studies reported intraobserver repeatability coefficients for AP aortic diameter measurements of 1·6-4·4 mm. These were below the 5-mm level regarded as acceptable by the UK and USA AAA screening programmes. Five studies had interobserver reproducibility below the level of 5 mm. Four studies, however, reported poor reproducibility (range from -2 to +5·2 to -10·5 to +10·4); these differences may have had a significant clinical impact on screening and surveillance.

CONCLUSION

The studies used different methodologies with no standardized measurement techniques. Measurements were taken by observers from different medical disciplines of varying grade and levels of training. Standard training and formal quality assurance of ultrasound measurements are important components of an effective AAA screening programme.

Systemic MCP1/CCR2 blockade and leukocyte specific MCP1/CCR2 inhibition affect aortic aneurysm formation differently

OBJECTIVE

CCR2, the receptor for monocyte chemoattractant protein 1 (MCP1), is involved in atherosclerosis and abdominal aortic aneurysms (AAAs). Here, we explored the potential beneficial blockade of the MCP1/CCR2 pathway.

METHODS

We applied an AAA model in aging apolipoprotein E deficient mice with pre-existing atherosclerotic lesions. These mice were subjected to two therapeutic strategies. First, a dominant negative form of MCP1 was overexpressed in femoral muscles, resulting in circulating levels of MCP1-7ND (7ND), competing with native MCP1. In the second approach, bone marrow transplantation was performed using bone marrow cells that were infected with a lentiviral construct containing siRNA for CCR2, to specifically inhibit only leukocyte CCR2 expression.

RESULTS

Both strategies did not influence lesion size of the advanced atherosclerotic plaques. However, 7ND induced a more fibrous plaque phenotype. Yet, surprisingly a trend in increased number and severity of AAA was observed in the 7ND group. Smooth muscle cells in the aneurysm showed decreased phosphorylated signal transducer and activator of transcription five (STAT5, P<0.01) in the 7ND group, which is indicative for a decreased proliferative and migratory (wound healing) response. This presumably resulted in the increased AAA development. In contrast, siRNA-induced inhibition of CCR2 in leukocytes led to a significant inhibition in aneurysm formation. In conclusion, systemic inhibition of the MCP1/CCR2 pathway leads to a fibrous plaque phenotype in the advanced atherosclerotic lesions, but to potential adverse effects on AAA formation, implying that for a beneficial overall therapeutic approach, specific inhibitory targeting of leukocyte CCR2 will be essential.

Gender differences in abdominal aortic aneurysms

Abdominal aortic aneurysms (AAAs) comprise the tenth leading cause of death in Caucasian males 65 to 74 years of age and accounted for nearly 16,000 deaths overall in 2000. Therefore, understanding the pathophysiology of AAAs is an important undertaking. Clinically, multiple risk factors are associated with the development of AAAs, including increasing age, positive smoking history, and hypertension. Male gender is also a well-established risk factor for the development of an AAA, with a 4:1 male to female ratio. The reason for this gender disparity is unknown. The pathogenesis of AAAs formation is complex and multifactorial. Histologically, AAAs are characterized by early chemokine-driven leukocyte infiltration into the aortic wall. Subsequent destruction of elastin and collagen in the media and adventitia ensues owing to excessive local production of matrix-degrading enzymes and is accompanied by smooth muscle cell loss and thinning of the aortic wall. At present, no medical therapies are available to treat patients with aortic aneurysms, using only the crude measurement of aortic diameter as a threshold for which patients must undergo life-threatening and costly surgery. Defining the early mechanisms underlying gender-related differences in AAA formation is critical as understanding differences in disease patterns based on gender may allow us to develop new translational approaches to the prevention and treatment of patients with aortic aneurysms.